1. Field of the Invention
The present invention relates to an ultrasonic diagnostic apparatus in which an ultrasonic probe transmits a signal, which is obtained by transmitting and receiving ultrasonic waves and thereby imaging organs and so on within a living body, to an ultrasonic diagnostic apparatus main body via wireless communication. Further, the present invention relates to an ultrasonic probe to be used in such an ultrasonic diagnostic apparatus.
2. Description of a Related Art
In medical fields, various imaging technologies have been developed for observation and diagnoses within an object to be inspected. Especially, ultrasonic imaging for acquiring interior information of the object by transmitting and receiving ultrasonic waves enables image observation in real time and provides no exposure to radiation unlike other medical image technologies such as X-ray photography or RI (radio isotope) scintillation camera. Accordingly, ultrasonic imaging is utilized as an imaging technology at a high level of safety in a wide range of departments including not only the fetal diagnosis in obstetrics, but also gynecology, circulatory system, digestive system, and so on.
The principle of ultrasonic imaging is as follows. Ultrasonic waves are reflected at a boundary between regions having different acoustic impedances like a boundary between structures within the object. Therefore, by transmitting ultrasonic beams into the object such as a human body and receiving ultrasonic echoes generated within the object, and obtaining reflection points, where the ultrasonic echoes are generated, and reflection intensity, outlines of structures (e.g., internal organs, diseased tissues, and so on) existing within the object can be extracted.
Generally, in an ultrasonic diagnostic apparatus, an ultrasonic probe including plural ultrasonic transducers (vibrators) having transmitting and receiving functions of ultrasonic waves is used. The ultrasonic probe and an ultrasonic diagnostic apparatus main body are often connected via a cable. However, in order to remove the burden of using the cable, ultrasonic diagnostic apparatuses of a wireless communication type for performing wireless information communication between the ultrasonic probe and the ultrasonic diagnostic apparatus main body are being developed. In the ultrasonic diagnostic apparatuses of a wireless communication type, reception condition of a radio signal varies depending on arrangement situations of the ultrasonic probe and the ultrasonic diagnostic apparatus main body.
As a related technology, Japanese Patent Application Publication JP-P2007-275087A discloses an ultrasonic diagnostic apparatus for establishing wireless connection between an ultrasonic diagnostic apparatus main body and a specific ultrasonic probe by wirelessly transmitting probe identification information from an ultrasonic probe to the ultrasonic diagnostic apparatus main body so that the ultrasonic diagnostic apparatus main body identifies the ultrasonic probe corresponding to the probe identification information.
However, in the case where there are plural connectable ultrasonic probes and plural ultrasonic diagnostic apparatus main bodies in a range where wireless communication is enabled, an operation for setting or the like is complicated in order to reliably establish wireless communication between a specific ultrasonic probe and a specific ultrasonic diagnostic apparatus main body to be used, and there is a danger of improper connection when an error occurs in the operation. Further, in the case where wireless communication condition is poor, false recognition of the ultrasonic probe may occur at establishment of wireless communication. In this case, a different kind of control is made by the ultrasonic diagnostic apparatus main body and an abnormal movement may occur, and therefore, there is a possibility that a problem such as a defective image may occur.
By the way, in the ultrasonic diagnostic apparatus, there is a request for forcible management of availability of connection between an ultrasonic probe and an ultrasonic diagnostic apparatus main body in order to prevent, for example, unwanted infection caused when an ultrasonic probe, which was used by one operator and requires sterilization treatment, is carelessly used by another operator.
As a related technology, Japanese Patent Application Publication JP-P2008-61938A discloses a technology for managing a condition of an ultrasonic probe when the ultrasonic probe is disconnected from an ultrasonic diagnostic apparatus main body and not used. The ultrasonic probe includes a handle part for transmitting and receiving ultrasonic waves, a connector connected to the ultrasonic diagnostic apparatus main body, for mediating supply of power and transmission and reception of signals for ultrasonic diagnoses, an internal power supply capable of supplying power to the inside when the connector is detached from the ultrasonic diagnostic apparatus main body, and condition managing means supplied with power from the internal power supply, for managing a condition of the ultrasonic probe.
The ultrasonic probe disclosed in JP-P2008-61938A has a function of managing the condition of the ultrasonic probe when not used, and notifying an operator of the condition. However, an operation for sequentially detecting the condition of the ultrasonic probe is necessary, and attention should be given to reduction in the remaining power of the internal power supply.